We will study the differences in cellular protein expression between normal and tumoral kidney tissues as well as the profile of protein expression in different tumor types of renal neplasms, using proteomics technology. The continuation of this line of work will hopefully lead to the discovery of new molecular markers important in the diagnosis and treatment of renal cancer. We will develop techniques that assist in the identification of proteins in paraffin-fixed tissues. Comparison analyses will be performed using frozen tissues.